elasticsearch mapping for Friend to Friend list

To answer your first question

so is this good to syncing done in real time 50-100 TPS or in future it will create problem

As of version ES6.0, Multi level nesting is automatically supported, and detected, resulting in an inner nested query to automatically match the relevant nesting level (and not root) if it exists within another nested query. But there is a caveat, indexing a document with 100 nested fields actually indexes 101 documents as each nested document is indexed as a separate document. To safeguard against ill-defined mappings the number of nested fields that can be defined per index is usually limited to 50 using the index.mapping.nested_fields.limit . This setting allows you to limit the number of field mappings that can be created manually or dynamically, in order to prevent bad documents from causing a mapping explosion. So to answer your question, this is fine, but as your data grows, it becomes more complicated to manage and you risk the danger of a mapping explosion.

To answer your second question

We need to create complex queries for updating the data because we are managing friend list in 2nd level. so how to create advance scripting in painless, I have checked this in Google but not found anything in detail.

You might need to present some context here to be able to understand why your approach is necessary, but basically, in a social profile context, managing a friends list as you are doing is always a bad idea, especially if you anticipate scaling in the future. It may work for smaller use-cases, but it does not work very well when you scale. This is because, the relationships become more sophisticated and you will end up having too many multi nested objects. As mentioned, all factors kept at a constant, you might want to look at a graph database for this kind of a scenario. You could, however, have other reasons to your approach which is why you might want to enumerate your context so we can better advise.

Hope this helps!!